Electrical contact sockets with incluned elastic wires and in methods for their manufacture

ABSTRACT

The contact socket is constituted by a tubular element inside of which inclined metallic wires are stretched, the ends of the wires being gripped between the outer surface of the tubular element and a tubular part open on one side and closed on the other by a transverse wall. The outer surface of the element, at least on the open side of the part, is provided with gripping projections.

United States Patent [191 Bonhomme 1 Jan.7, 1975 1 1 ELECTRICAL CONTACT SOCKETS WITH INCLUNED ELASTIC WIRES AND IN METHODS FOR THEIR MANUFACTURE [75] Inventor: Francois Robert Bonhomme,

Saint-Cloud, France [73] Assignee: Connectronics Corporation, New

York, NY.

[22] Filed: Dec. 15, 1972 [21] Appl. No.: 315,328

[30] Foreign Application Priority Data Dec. 17, 1971 52 US. Cl. 339/256- [51] Int. Cl H0lr 13/24 [58] Field of Search...,..... 339/256 R, 256 S, 256 P,

339/258 A, 258 R, 258 C, 262

[56] References Cited UNITED STATES PATENTS 2,115,010 4/1938 Douglas 339/258 C France 71.45613 J& 3 .16 36 Huston 339/256 R Bonhomme 339/256 R FOREIGN PATENTS OR APPLICATIONS 942,835 11/1963 Great Britain 339/256 S Primary ExaminerWerner H. Schroeder Assistant Examiner-Wai M. Chan Attorney, Agent, or FirmLarson, Taylor and Hinds [57] ABSTRACT The contact socket is constituted by a tubular element inside of which inclined metallic wires arestretched,

the ends of the wires being gripped between the outer surface of the tubular element and a tubular part open on one side and closed on the other by a transverse wall. The outer surface of the element, at least on the open side of the part, is provided with gripping projections.

9 Claims, 6 Drawing Figures minnow 1191s 3,858,962

SHEET 10F 2 34. qzy 36 J The invention relates to improvements in electrical 5 connector sockets, for plug and socket assemblies of the type whichcomprise, inside a rigid tubular element,

at least one rectilinear metallic and elastic wire, (that is, the wire is rectilinear when not pushed out by the presence of a plug) which is inclined with respect to the axis of this element and of which the ends are fixed by crimping at the respective ends of said element; and it relates more particularly because it is in this case that its application seems to be of most interest, but not exclusively amongst these sockets, to those which each comprise several wires the positions of which are derived geometrically from one another by rotation around the abovesaid axis (the wires being thus positioned along one of the families of generators of a hyperboloid revolution). The invention relates, also, to methods of manufacturing these connecting sockets.

lnapplicants prior U.S. Pat. No. 3,470,527 there are described electrical connector devices which consisted, especially, as regards the sockets of the type. concerned, in arranging them so that the two ends of the or of each wire are crimped by pinching between the respective ends of the tubular element and the inner wall of a single tubular part surrounding said element.

To manufacture such sockets, there had been proposed, according to the aforesaid patent:

, a method with consists of arranging the or each wire inside the tubular element, by curving one of its ends against the terminal edge of the tubular element; in threading the latter inside the tubular part by making the said edge pass first until the end concerned of the or of each wire is pinched between the terminal edge of the tubularelement and a transverse wall of the outer tubular part; and in deforming if necessary the end of this part which is at the greater distance from this transverse wall so as to grip (or to contribute to gripping) against the tubularelement the other end of of the tubular element against-the rims of the latter,

once said element and the corresponding wires have been mounted on the mandrel; and means adapted to push said tubular part around the tubular element and against the curved ends of the wires.

It is an object of the invention to render the abovesaid sockets such that their manufacture is easier than hitherto and that their wires are held therein more securely.

To this end, the invention proposes, in the first place, an electrical contact socket, for plug and socket assemblies, which comprises, inside a rigid tubular element, at least one rectilinear metallic and elastic wire (that is, the wire is rectilinear when not pushed out by the presence of a plug) which is inclined with respect to the axis of this element and of which the ends are fixed by crimping to the respective ends of said element, which sleeve comprises, preferably, several wires the positions of which are derived geometrically from one another by rotation around the abovesaid axis (the wires thus being positioned along one of the families of generators of hyperboloid of revolution), the two ends of the or of each wire being crimped by pinching between the respective ends of the tubular element and the inner wall of a single tubular part surrounding said element, this part being open on one side and closed on the other side by a transverse wall, which sleeve is characterised by the fact that the (outer) tubular part possesses a smooth inner wall and the (inner) tubular element an outer wall provided with gripping projections, at least over its portion in the vicinity of the open side of the tubular part.

The invention proposes, in the second place, a method ofmanufacturing the abovesaid sockets which consists in arranging the or each wire inside the tubular element, in curving one of its ends against a terminal edge of the tubular element; in threading the latter inside the tubular part by making the said edge pass first until the end concerned of the or of each wire is pinched between the terminal edge of the tubular element and a transverse wall of the outer tubularpart; and, if necessary, in deforming the end of this part which is most distant from the transverse wall so as to clamp (or to contribute to clamping)against the tubular element the other end of the or of each wire, this method being characterised by a preliminary phase consisting in rendering the inner wall of the (outer) tubular part smooth and in providing gripping projections on the outer wall of the (inner) tubular element, at least over its portion which has to be in the vicinity of the open side of the tubular part. v

And it will, in any case, be well understoodby means of the additional description which follows, as well as of the accompanying drawings, which description and drawings are of course given primarly by way of indication and not intended to be limiting in character. 7

In the drawings:

FIG. 1, shows in axial section the tubular element forming a portion of the socket constructed according to the present improvements.

FIGS. 2 to 6 illustrate diagrammatically, the successive manufacturing operations of the socket comprising the tubular element of FIG. 1.

According to the invention and more especially according to that of its type of application, as well as according to those embodiments of its various parts, to which would appear that preference should be given, in order to construct an electrical contact "socket which comprises, inside a rigid tubular element 1, several rectilinear wires 2 the positions'of which are derived geometrically from one another by rotation around the axis X-X of the element 1 and inclined with respect to this .axis, procedure is as follows or in similar manner.

ductor (not shown) which, with the conductor attached to the plug (not shown) for insertion in the socket, can ensure the continuity of an electrical circuit.

This construction enables mechanical continuity of the socket to be ensured giving it a greater robustness when a plug is introduced therein in a manner which is not strictly axial.

-To manufacture such a socket, as shown in FIGS. 2

'to 6, the wires 2 are arranged inside the tubular elecut away as shown in the figures so as to grip againstthe element l the other ends 2b of the wires 2.

To put this method into operation, recourse may be had to a machine constituted:

by a mandrel 30 having afirst cylindrical'portion 31,

of which the radius r (FIG. 2) is equal to the. inner radius of the tubular element 1 and which possesses positioning slots32 for the wires 2, and a second cylindrical portion 33 which follows the first and-of which the radius R (FIG. '2) is equal to the outer radius of the ele ment 1 increased by the diameter of the wires'2;

-by means(not shown) adapted to fold the two ends and 2b of each wire 2 towards the outsideof the tubular element 1 against the rims la and lb of the latter,- once the said element 1 and.the wires 2 have been mounted on the mandrel 30;

and by means'(no.t shown) adapted topush the tubular part 3 around the tubular element'l and against the curved ends 2d and 2b of the wires 2.

As shown in FIGS. 2 to 6, the cylindrical portion 33 of largest diameter can be constituted by a tube 35 fitted onto the body-of the mandrel 30 i the latter.

To manufacture the socket l, 2, 3, the procedure is as followspFirstly an element 1 is threaded onto the portion 31 of'the mandrel 30, then-the wires 2 are placed in position in the slots 32 of said part 31. (FIG. 2)*by folding-back towards the outside the ends 2a and 2b of thewires 2. Then, the part 3 is pushed towards the left (FIGS. 3 to 5) which folds the ends 2a against the inner wall of the part 3 and the outer wall of the element 1- (FIG. 4). The part 3 continues its displacement towards the left, until the ends 20 of the wires are pinched between the edge la 0f the element 1 and the wall of the bottom 5 of the part 3 (FIG. 6). To finish the socket, the ends 2b of the wires can then be crimped by deformation of the part 3.

On engagement of the-tubular part 3 on the tubular and slidable on the gripping projections can result'from the presence of annular grooves 39 (FIG. 1) which provide between them gripping projections 38 having an annular shape.

As shown in the Figures, the projections 38 are advantageously of a saw-tooth'profile, each tooth being bounded by anedge approximately perpendicular to the axis of the element, on the side for introducing the part 3 during assembly, and by an inclined edge on the other side.

Contrary to the embodiment shown, the projections '38 can be distributed symmetrically to the right and to the left (in the Figures) of the tubular element 1 so that in automatic manufacture, themeanswhich have to bring successively the elements 1 onto the mandrel do not have to select between two possible orientations for these elements. e The projections 38 can be formed by means of operations similar to thoseof forming screw-threads (by rolling, by means of combs and similar operations). The polishing of the bore 37 of the tubular part 3 can be achieved, if this part is of a simple shape, by deep stamping or, if it is of complicated outer shape, by screw-cutting, electrochemical protection and forming by means of a punch of tungsten carbide.

,There is thus obtained a socket of which the method of manufacture is free of the defect indicated above. In

fact, the wall 37 of the part-3, since it is smooth, only element 1, the mandrel 30 is fixed and the tubular element 1 is immobilised by contactwith a shoulder 36 of the mandrel. The ends 2a of the wires are oriented in such a way that the displacement of the tubular part 3 (according to the successive phases of FIGS. 3 to 6) does not modify their respective positions but tends to wind them on the edge la of the element 1. On the contrary, the ends 2b are oriented so that the displacement of the tubular part tends to make them withdraw or to unwind from the edge lb.

To eliminate this drawback, according to the invention, the inner wall 37 of the tubular part 3 is made smooth and catch projections 38 are provided on the outer wall of the tubular element 1, at least on its front exerts a limited longitudinal'force on theends 2b of the wires 2. Moreover, these endsbeing held by the projection 38, they do not tend to follow the movement'of the As is self-evident and as emerges already from the 1 foregoing, the invention is in no way'limited to those of its typesof applications, nor to those embodiments of its various parts, which have been more'especially indicated; it encompasses, 'on the contrary, all modification's.

I I claim: s 4

1. Electrical connector socket, for plug and socket assemblies, which socket comprises in combination an inner rigid tubular element having an outer wall, a series of resilient conducting wires, each having ends carried by respective ends of said tubular element so as to extend obliquely to the longitudinal axis of said tubular element in a position where' the transverse crosssection of the space between the wires has limited area, resilient pressure, contact engagement with said plug as the plug is inserted into said tubular element, each said wire having each of its ends hooked around the corresponding ends respectively of said tubular element and being straight when not in engagement with said plug, and an outer, integral, tubular part coaxially surrounding said tubular element, having a smooth inner surface and having an inner diameter slightly greater than the outer diameter of said tubular element and of a" length a little greater than. the length of said tubular element, the two ends of each said wire being crimped, by means of the smooth inner wall of said tubular part and the outer wall at the ends of the tubular element, said tubular part being open at one end and closed at the other end by a transverse wall, said outer wall of said inner ridge tubular element being provided with a plurality of essentially annular gripping projections, at least over its portion in the neighbourhood of the open end of the tubular part for gripping the wires against movement releach tooth being bounded by an edge approximately perpendicular to the axis of the element, on the side for introducing the part during assembly, and by an inclined edge on the other side.

4. Electrical connector socket according to claim 1, wherein said projections are distributed symmetrically at each end of said tubular element.

5. Electrical connector socket according to claim 1, wherein said projections are formed by ridges of a screw-thread.

6. Method of manufacturing an electrical connector socket, for plug and socket assemblies, which socket comprises in combination an inner rigid tubular element, a plurality of resilient conducting wires, each having ends carried by respective ends of said tubular element so as to extend obliquely to the longitudinal axis of said tubular element in a position where the transverse cross-section of the space between the wires has limited area, resilient pressure, contact engagement with said plug as it is inserted into said tubular element, said wires each having each of its ends hooked around the corresponding ends respectively of said tubular element and being straight when not in engagement with said plug, and an outer, integral, tubular part coaxially surrounding said tubular element, having a smooth interior surface and an inner diameter slightly greater than the outer diameter of said tubular element and having a length a little greater than the length of said tubular element, the two ends of said wire having been crimped, by means of said tubular part having a smooth inner wall, between the respective ends of the tubular element and the inner wall of said tubular part, said tubular part being open at one end and closed at the other end by a transverse wall, said inner rigid tubular element having an outer wall provided with a plurality of essentially annular gripping projections, at least over its portion in the neighbourhood of the open end of the tubular part, which method comprises the steps of arranging each said wire obliquely inside said tubular element, by curving first and second of its ends respectively around first and second terminal edges of the tubular element; engaging the second curved end by means preventinglon'gitudinal movement of the wire away from the tubular element, forcing the tubular element into the tubular part by making the said first terminal edge pass over said smooth inner wall of the tubular part until said one end of each wire is pinched between said terminal edge and said transverse wall; and also by causing said gripping projections to securely grip the said second ends of said wires which are most distant from said transverse wall against movement relative to the tubular element and so as to limit the tendancy of the wires to move with said tubularpart.

7. Method according to claim 6, including deforming the end of said tubular part which is most distant from said transverse wall so as to produce a clamping action on the other end of each wire, against the tubular element.

8. Method according to claim 6, wherein the said step of causing the gripping projections includes using projections which are screw-threads.

9. Method according to claim 6, wherein the said step of causing the gripping projections includes using projections which are annular ridges. 

1. Electrical connector socket, for plug and socket assemblies, which socket comprises in combination an inner rigid tubular element having an outer wall, a series of resilient conducting wires, each having ends carried by respective ends of said tubular element so as to extend obliquely to the longitudinal axis of said tubular element in a position where the transverse cross-section of the space between the wires has limited area, resilient pressure, contact engagement with said plug as the plug is inserted into said tubular element, each said wire having each of its ends hooked around the corresponding ends respectively of said tubular element and being straight when not in engagement with said plug, and an outer, integral, tubular part coaxially surrounding said tubular element, having a smooth inner surface and having an inner diameter slightly greater than the outer diameter of said tubular element and of a length a little greater than the length of said tubular element, the two ends of each said wire being crimped, by means of the smooth inner wall of said tubular part and the outer wall at the ends of the tubular element, said tubular part being open at one end and closed at the other end by a transverse wall, said outer wall of said inner ridge tubular element being provided with a plurality of essentially annular gripping projections, at least over its portion in the neighbourhood of the open end of the tubular part for gripping the wires against movement relative to the tubular element.
 2. Electrical connector socket according to claim 1, said plurality of said wires positioned in relative positions derived geometrically from one another by rotation around said axis along one of the families of generators of a hyperboloid of revolution.
 3. Electrical connector socket according to claim 1, wherein each said projection has a saw-tooth profile, each tooth being bounded by an edge approximately perpendicular to the axis of the element, on the side for introducing the part during assembly, and by an inclined edge on the other side.
 4. Electrical connector socket according to claim 1, wherein said projections are distributed symmetrically at each end of said tubular element.
 5. Electrical connector socket according to claim 1, wherein said projections are formed by ridges of a screw-thread.
 6. Method of manufacturing an electrical connector socket, for plug And socket assemblies, which socket comprises in combination an inner rigid tubular element, a plurality of resilient conducting wires, each having ends carried by respective ends of said tubular element so as to extend obliquely to the longitudinal axis of said tubular element in a position where the transverse cross-section of the space between the wires has limited area, resilient pressure, contact engagement with said plug as it is inserted into said tubular element, said wires each having each of its ends hooked around the corresponding ends respectively of said tubular element and being straight when not in engagement with said plug, and an outer, integral, tubular part coaxially surrounding said tubular element, having a smooth interior surface and an inner diameter slightly greater than the outer diameter of said tubular element and having a length a little greater than the length of said tubular element, the two ends of said wire having been crimped, by means of said tubular part having a smooth inner wall, between the respective ends of the tubular element and the inner wall of said tubular part, said tubular part being open at one end and closed at the other end by a transverse wall, said inner rigid tubular element having an outer wall provided with a plurality of essentially annular gripping projections, at least over its portion in the neighbourhood of the open end of the tubular part, which method comprises the steps of arranging each said wire obliquely inside said tubular element, by curving first and second of its ends respectively around first and second terminal edges of the tubular element; engaging the second curved end by means preventing longitudinal movement of the wire away from the tubular element, forcing the tubular element into the tubular part by making the said first terminal edge pass over said smooth inner wall of the tubular part until said one end of each wire is pinched between said terminal edge and said transverse wall; and also by causing said gripping projections to securely grip the said second ends of said wires which are most distant from said transverse wall against movement relative to the tubular element and so as to limit the tendancy of the wires to move with said tubular part.
 7. Method according to claim 6, including deforming the end of said tubular part which is most distant from said transverse wall so as to produce a clamping action on the other end of each wire, against the tubular element.
 8. Method according to claim 6, wherein the said step of causing the gripping projections includes using projections which are screw-threads.
 9. Method according to claim 6, wherein the said step of causing the gripping projections includes using projections which are annular ridges. 